Bissell truck \Bis"sell truck\ A truck for railroad rolling stock, consisting of two ordinary axle boxes sliding in guides attached to a triangular frame; -- called also pony truck.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Pony \Po"ny\, n.; pl. Ponies. [Written also poney.]

[Gael. ponaidh.]

1. A small horse.

2. Twenty-five pounds sterling. [Slang, Eng.]

3. A translation or a key used to avoid study in getting lessons; a crib. [College Cant]

4. A small glass of beer. [Slang]

Pony chaise, a light, low chaise, drawn by a pony or a pair of ponies.

Pony engine, a small locomotive for switching cars from one track to another. [U.S.]

Pony truck (Locomotive Engine), a truck which has only two wheels.

Pony truss (Bridge Building), a truss which has so little height that overhead bracing can not be used.

Source: Webster's Revised Unabridged Dictionary (1913)